This invention relates to an elongate connector for securing a vertically disposed structural member to a concrete foundation. The connector is partially embedded in a concrete foundation and fasteners attach the connector to the structural member to be anchored. According to the present invention, the embedded portion of the connector is formed with a keyhole opening or slot that, in the preferred embodiment, can receive the intermediate head and hold the shank of a standard double-headed nail. The slot is located in the embedded portion of the connector such that the tip of the nail can be partially driven into a wooden form board or other member. A form board, as used here, is a member used to define the boundaries of a poured concrete foundation or other cementitious member. By connecting the double-headed nail to the connector and to the form board the nail serves as a brace for the connector. This helps to keep the connector plumb, during the pouring of the concrete.
As is evidenced by such previous patents as U.S. Pat. No. 5,150,553, granted to Alfred D. Commins on Sep. 29, 1992, and U.S. Pat. No. 5,813,182, also granted to Alfred D. Commins on Sep. 29, 1998, connectors that are partially embedded in a concrete foundation and are attached to a vertically disposed structural member by means of fasteners are well known in the prior art. U.S. Pat. Nos. 5,150,553 and 5,813,182 are incorporated herein by reference. These connectors, commonly called strap anchors, have been widely accepted by builders due to the ease with which they can be installed, and their relatively low cost in comparison to other types of anchors.
Strap anchors, as described above, are generally elongate members. They protrude above the upper level of the foundation considerably. Strap anchors are generally designed to be attached with light fasteners such as nails. A large number of nails are generally needed to make a secure attachment between the connector and the structural member. Thus the upper portion of the connector must be rather long to accommodate the larger number of fasteners.
The fact that a considerable portion of a strap anchor protrudes above the level of the foundation raises problems during the pouring of the cement around the strap anchor. Generally, strap anchors are attached to the outer form boards near the tops of the form boards by means of typical fasteners such as nails. The inventor has found that during a typical foundation pour, the flowing concrete has a tendency to move the strap anchor out of the alignment it originally had when it was attached to the form board. This is thought to occur because the attachment of the strap anchor to the form board is insufficient.
To improve the connection between the form board and the strap anchor so that the anchor is less likely to be moved out of its original alignment, the inventor has devised an additional attachment between the form board and the strap anchor.
It is an object of the present invention to provide an improved connection and a method of making that connection between a connector and the form from which it is suspended, so that the connector remains in alignment during the pouring of a cementitious member.
The improved connection is achieved by making an additional attachment between the connector and the form. The additional attachment is made possible because the embedded portion of the connector is formed with a opening that can receive and hold the shank of a nail that is partially driven into a form board.
In one form of the invention the additional attachment is made with a double-headed nail. Preferably, the embedded portion of the connector holds the upper portion of the shank of the double-headed nail between the end most head and the intermediate flanges or head of the nail.
In another form of the invention, the nail is held by a narrow or constricted portion of a specially shaped opening, having both an enlarged portion and a constricted portion. This shaped opening can be keyhole-shaped. The constricted portion of the opening is shaped so that the side of the opening lies closely adjacent to the shank of the fastener near at least two points on the shank of the fastener. The constricted portion of the opening can be shaped with two substantially opposed side edges spaced just enough from each other to receive the shank of the nail. The enlarged portion of the opening can be circular in shape to closely receive the head of a fastener.
To make the connection the nail is moved into position by inserting the nail through the wide portion of the opening such that the shank is received thereby. The nail is driven partially into the form board. Then the shank of the fastener is slid out of the wide portion and into the narrow portion of the keyhole opening. The form board is preferably the same form board to which the strap anchor is already attached.